EUVD-2023-2893

Comprehensive Technical Analysis of EUVD-2023-2893

1. Vulnerability Assessment and Severity Evaluation

Vulnerability Description: The XWiki Platform, a generic wiki platform, has a vulnerability where the section URL parameter is not properly escaped. This flaw allows any user with read access to the document XWiki.AdminSheet to execute arbitrary code, including Groovy code. This vulnerability impacts the confidentiality, integrity, and availability of the entire XWiki instance.

Severity Evaluation: The vulnerability has a CVSS Base Score of 10.0, which is the highest possible score, indicating a critical severity. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H breaks down as follows:

• Attack Vector (AV): Network (N) - The vulnerability is exploitable over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal complexity.
• Privileges Required (PR): None (N) - No privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required.
• Scope (S): Changed (C) - The vulnerability affects a different security scope.
• Confidentiality (C): High (H) - The vulnerability has a high impact on confidentiality.
• Integrity (I): High (H) - The vulnerability has a high impact on integrity.
• Availability (A): High (H) - The vulnerability has a high impact on availability.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unauthenticated Users: Any user, including unauthenticated users, can exploit this vulnerability by crafting a malicious URL that includes Groovy code.
• Authenticated Users: Authenticated users with read access to the XWiki.AdminSheet document can also exploit this vulnerability.

Exploitation Methods:

• Code Injection: Attackers can inject Groovy code into the section URL parameter, which will be executed by the XWiki instance.
• Remote Code Execution (RCE): The injected code can perform various malicious actions, such as data exfiltration, unauthorized modifications, or denial of service.

3. Affected Systems and Software Versions

Affected Versions:

• XWiki Platform versions prior to 14.10.14
• XWiki Platform versions 15.0-rc-1 and prior to 15.5.1

Specific Components:

• org.xwiki.platform:xwiki-platform-administration-ui
• org.xwiki.platform:xwiki-platform-administration

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Upgrade: Upgrade to the patched versions: 14.10.14, 15.6 RC1, or 15.5.1.
• Manual Fix: Apply the fix in commit fec8e0e53f9 manually if upgrading is not possible.
• Access Control: Remove view rights for guests from the XWiki.AdminSheet document to prevent unauthenticated users from exploiting the vulnerability.

Long-Term Mitigation:

• Regular Updates: Ensure that the XWiki Platform is regularly updated to the latest stable version.
• Access Controls: Implement strict access controls and regularly review permissions to minimize the attack surface.
• Monitoring: Implement monitoring and logging to detect and respond to any suspicious activities.

5. Impact on European Cybersecurity Landscape

Regulatory Compliance:

• GDPR: Organizations using XWiki Platform must ensure that personal data is protected. This vulnerability could lead to data breaches, violating GDPR regulations.
• NIS Directive: Critical infrastructure operators using XWiki Platform must address this vulnerability to comply with the NIS Directive, which mandates robust cybersecurity measures.

Industry Impact:

• Wide Adoption: XWiki Platform is widely used in various industries, including education, healthcare, and government. The vulnerability poses a significant risk to these sectors.
• Supply Chain: Organizations relying on third-party services that use XWiki Platform should ensure their suppliers have addressed this vulnerability to avoid supply chain attacks.

6. Technical Details for Security Professionals

Technical Overview:

• Vulnerable Component: The section URL parameter in the XWiki Platform's administration sections.
• Exploitation: The vulnerability arises from improper escaping of the section URL parameter, allowing code injection.
• Mitigation Commit: The fix is available in commit fec8e0e53f9fa2c3f1e568cc15b0e972727c803a.

Detection and Response:

• Detection: Implement intrusion detection systems (IDS) to monitor for suspicious activities related to the XWiki.AdminSheet document.
• Response: Develop an incident response plan that includes steps to isolate affected systems, apply patches, and notify relevant stakeholders.

References:

• GitHub Advisory: GHSA-62pr-qqf7-hh89
• NVD Entry: CVE-2023-46731
• GitHub Commit: fec8e0e53f9fa2c3f1e568cc15b0e972727c803a
• Jira Issue: XWIKI-21110

By addressing this vulnerability promptly and comprehensively, organizations can mitigate the risk of severe cybersecurity incidents and ensure compliance with relevant regulations.